Comminuted-fuel-feeding apparatus.



C. L.` HEESLER.

COMWHNUTED FUEL FEEDING MPARTUS.

WPLICATION FILED FMY 20| 1926.

www Ang. 21, mi?.

z SHEETSAHEET 2.

Mx/@M i lli o :Fuel

CHARLES L. HEISLER, OIE' `SCHEJSTE(lilik/5523's,, YORK.

COMMINUTED-FUELFEEDING APPARATUS.

Specification of Letters Patent.

resented sag. er, ier?.

Application filed May 20, 1916. Serial No. 98,846.

b all wtom t may concern 13e it inici/vn that l., CHAnLEs L. HEISLER, et" Schenectady, in the county of Schenectad.7 and State ot New York, have invented u. certain new and useful Improvement inv EComminuted Fuel Feeding Apparatus, o which improvement the following is a. specilicati n.

li/l y invention relates more particularly to means for controlling the flow of powdered fuel from a .hopper into an air blast which conveys the fuel and air mixture to a furnace. i i

The objects of my invention are to provide an eliiective and simple means for changing; the rate of feed when operating a toed .crew at practically constant speed; to provide inea-ns whereby the fuel lying upon and 4adjacent to the screw is continually agitatcd and moved along a path parallel with the screw in a manner to prevent clogging and to convey fuel to any desired number oit adjustable outlets arranged alone1 one, or more feed screws; to provide an effective safeguard against clogging the screw and related parte when one, or more feed outlets therefrom are closed; to provide a simple and effective hopper bottom and slide controlled outlet ports which will Shut ofi' and .permit ready access to any section ot the screw and iced valves without interrupting the operation of other feed screws that may be attached to the hopper bottom and to provide an improved orm olE tuel feed valve and supporting casings therefor.

.ln the accompanying drawings, Figure l, is an elevation, of which part is in section for the purpose of showing the application ot my improvement to a .pulverized' coal tondino' hopper of usual construction; Fig` il, a plan view of my improved hopper bottoni and arrangement or' feed screws; Fig. il. a. longitudinal sectional elevation thereof; lligr/ 4f, a diagrammatic plan yviewof the :toed screws; Fig. 5, a plan view of a :teed valve with screw omitted; Fig. 6, a sectional elevation thereof; Fig. 7, an end exterior view; Fig. 8, a bottom view thereof; Fig.

' il. :1. transverse sectional elevation taken on the vertical plane 9, 9, of Fig. 6.; Fig. l0, an

valve,v ligsll, and 12j, details of a. valve rising spacer.

lor the purpose of obtaining simplicity,

extremity of the hopper low cost of installation and maintenance, inl

the practice of my invention, it is preferred to drive several screws with a single motor, in preference to using en independent variable speed motor for each feed, therefore, as shown in Fig. l, a single motor l, supported on the hopper 2, is belted to a countershalt Q, from which the screws 3 and 4, are driven, preferably by belts and pulleys. I do not, however, limit myself to this arrangement of drive, as the screws may be' driven in any edective manner without departing from the spirit of my invention.

An outwardly projecting and horizontally disposed flange 2b, is formed on the lower 2, in a manner to form a support and bolting face for the multiported feed valve casing supporting member or hopper bottom 5, secured thereto by the bolts 2d. A plurality of hopper port closing slides 5b, 5, 5e, 57 and 5h, are mounted upon the bottom and over their corresponding outlet ports, 57', 5k, 51, 5m; 5, 5F, formed in the bottom. The pair of end slides 5a and 5h, are arranged to cover a transversely disposed conveyerscrew 6. The spaces inthe bottom between the slides 5", 5d and 5e, consist of thin sections 5S, and the allel adjoining screw 4L, said forming a cover over each of the feed valve casings 7, 7a, 7", 7d and 7e, which have feed discharge outlets 7, formed thereon as 'shown in Figs. 2 and 3. Evidently by closscrews may be removed bottom. lf desired, the hopper slides 5h, 5a, 5b,"5d and 5, could be closed to permit the removal, or examination ci the screw 3, without discontinuing the operation of the screw 4. ln like manner the screw s, could be removed by closing its slides 5f, 5g, 5?* and .5% without disturbing the' feed Screw '3.

The feed valve casings of the two screws Fig. 4, illustrates, diagrammatically, the

flow of fuel around two circuits formed by four parallelly disposed feed screws 10, 10a, 10b, 1G", and the three transversely disposed conveyer screws 11, 11JL and 11h. The transverse conveyer screws are shown disposed under the feed screws. Practice has demonstrated thata screw, when rotated, will not clog if the fuel is continually taken away from its discharge end, that is from the end toward which the fuel is carried. Furthermore, it was found that by maintaining a free discharge through the last valve, of a series of valves, fed by a screw, that is, the valve located at the dischargev end of the screw, the screw will not clog, nor when the `fuel is carried away from the discharge end by any other means, as for example, by the transverse conveyer screws, 11, 11:L or 11b, which are made use of when it is desired to make the feed valves adjustable so they can all be closed while the screws are rotating. Furthermore, when using a single screw and a plurality of feed valves, to govern the i feed without change of rotative speed, it is necessary to omit the adjustable feature on one feed valve, disposed at the discharge end of the screw, to insure a free outlet to all fuel conveyed thereto by the screw.

The feed valve and adjustment comprise a comparatively long movable valve sleeve 12, preferably made of copper tubing, dis

posed axially with the screw and which snugly embraces the screw 3, but with sufficient freedom to permit rotation of the screw and a longitudinal adjustment of the sleeve by means of the rack 12a, which meshes with a manually operable segmental pinion 13. This pinion is keyed to the valve feed adjusting shaft 13, and is inclosed within the valve casing 7, which Ihas adjusting shaft bearings Y", formed thereon. The sleeve end 12b, which protrudes into any of the hopper bottom outlet ports, is cut away on its upper side'to avoid reta'rding the flow of fuel to the screw. The opposite end is provided with pointed ends forming V shaped notches or ports 12e, adapted to enter the enlarged or bell end 14 of the stationary sleeve 14, in a manner to give a gradual adjustment of flow of the fuel which is conveyed thereto by the screw. The flow of fuel is completely shut off when the notch ports are covered by the stationary sleeve bell end 14a. To give perfect freedom and a steady flow to the fuel in its passage from the screw into the casing 7, an annulappassage 15a, comy municating with the casing 7, is formed in the valve cap 15, in a manner to register with the ports 12e. I do not vlimit myself to cutting the V notches in the valve sleeve 12, as they evidently can be cut in the bell end 14a. However, preference is given to the construction illustrated because the powdered fuel cannot be packed at the bottom cf the bell by the pointed ends of the valve sleeve. The helix 3b, is formed from a rectangular piece of steel andis forced tightly upon the screw shaft. This helical member has a shear, or sliding action over theVports and edectively clears them from coal and prevents clogging. The movement of the helix over the several ports gives a very uniform delivery of fuel by causing it to discharge freely and continuously through each succeeding port into the annular space 15a, formed around the belled and notched valve sleeve ends. To prevent leakage, a felt packing box 12D, is formed around and near the right end of the sleeve 12. The cap 15, is fastened to the valve casing 7, by the bolts 15". The casing 7, is fastened to the hopper bottom by bolts 7l', which pass through the holes 7X, formed in the casing. The cap 15, serves as `a guide for the sleeve 12, secures the stationary sleeve 14 in place and prevents undesired flow of fuel into the casing. The bearing 18a, formed on the valve casing spacer 18, gives a support to the protruding end of the valve sleeve 12, to prevent the gear and rack action from cramping it in the casing and on the screw. These semi-cylindrical spacers are made the same length as the casings, for interchangeability and simplicity in manufacture.

The casing spacer 18, is preferably cast separate from the casing, as shown, this construction being preferred because it permits a ready removal to give convenient access to the screw after closing,r the. corre* sponding hopper slide to prevent a discharge of fuel, when it is necessary to remove a foreign substance from the feeder. The spacer forms a removable feed screw chamber and incloses a section of the screw and space directly under a hopper port and slide. The spacer is fastened to the multiported member or hopper bottom 5 by the bolts 18".

What l claim is:

1. In a comminuted fuel feeder, the combination of a hopper bottom having a plurality of alined fuel outlets, a shut-olf slide for each outlet, a feed screw beneath said outlets, a feed valve casing surrounding said screw between adjacent outlets and having a discharge opening below said" screw, a sleeve iXed to each of said casings around said screw and having an enlarged end, a valve sleeve slidable in each of said casings and having a notched end fitting within said enlarged end of the fixed sleeve, and means to slide each of said valve sleeves to control the rate of feed.

2. The combination in a comminuted fuel feeder, of a rotary feed screw, a feed valve i n enl, of seid slidahle f and from the other sleeve for the ineens for adjusting one of the sleeves to purpose of governing 'the feed..

ln a comininuted fuel feeder, the com. hination oi' a hopperhottom having` a fuel outlet, a feed screw beneath the same, a' casing, having a iuel discharge opening, mounted beneath said'hottoin to one eide ot' said outlet and supporting said screw, said casing having a semi-circular recess formed .in its upper part, a sleeve secured. in said casingv and havingan enlarged end lying within said recess, a valve sleeve slidahly mounted in said casing and having .a notched end fitting within said enlarged end, the upper part of said vulve Sleeve being out away beneath said outlet to receive the fuel therefrom, and means to slide said valvesleeve.

4. The combination ina coznluinuted fuel feeder, oit a rotary teed screw, an adjustable :leed valve screw, a casing having a fuel outlet, a feed port :termed around the valve sleeve and screw, an annular passage arranged around the valve sleeve and screw in a manner to permit a free flow of fuel from the feed port at any point erom-1d the valve sleeve and. .:crev to said outlet, and means for adjusting said valve sleeve to govern the feed.

5. The continuation in a colnininutcd t'uel feeder, olf rotary feed screw, an adjustahle :toed valve. sleeve disposed axially with the efrerp, means for adjusting the valve Sleeve, 'a easing having; a fuel outlet and embracing' a veection of said screw, and n can adapted to cover a section of the screw and valresleeve in a manner to prevent an. un 'reel iloiv oifjtuel through the casing. ln a conuninuted fuel `totaler, the coin-- titration of a hopper bottoni provided with a. plurality ot fuel outlets, a cuter? slide for each outlet, a valve casing secured to said hottem between each adjacent pair el. out lets, a spacer beneath each outlet between said caeings, a elidable velve sleeve in each easing having van'opein 'portion t-.nttentling` into and supported hy said spacer and a tulmlarportion having' a notched end Within said casing, a xed sleeve in seid easing having' an enlarged end receiving the notched A sleeve, the upper part ol' said easing being enlarged around the en- `largged end oi said fixed sleeve, and. means to' actuute said sliduhle sleeve.

7. The eomhination in a comminuted -fuel feeder, of a rotary feed. screw, a easing inclosing' a section of the screw, and an adjustable sleeve feed valve having the upper portion ofits end protruding fromy the cas# .sleeve disposed axially with the" ing cut away to give a free ow of fuel to the screw,

`8. The combination in a comminuted fuel feeder, of a rotary feed screw, a casing inclosing,r a section ol' the Screw, an adjustable '65 sleeve feed valve having an end protruding from the casing, and a hearing adapted to support said protruding end for the purpose of preventing cramping of the sleeve Within the casing. 70

9. ln a comminuted fuel feeder, the eoml hination et a hopper having a plurality of rows ot fuel outlets in its bottom, the outlets in each row being staggered relatively to those in the'dadjacent rows, a cut-ofi7 slide for each outlet, valve casing's secured to the underside .of said bottom. between the adjacent outlets in each row and extending beneath the outlets, a feed screw journaled in said casings beneath each row of outlets, an independently operable :tuel valve /in each easing, and a common conduit cornmunicat` ing; uithall ot' said casings.

l0. ln a coniniinuted iuel feeder, the combination ot a rotary leed screw, a casing inclosing a eectionot the Same, and having a discharge outlet, a lon,.. ritudinall)7 slidalole valve sleeve surrmznding said screw in said casing, the end of said sleeve projectingwoutside said' casing; andy heing cut away at the top te receive the fuel, and fa supporting niernl'ler for said end.

ll. The eoinhination'in acomminuted fuel feeder, et a pluralityot valve casings havin feed out-lets formed therein, valves in said casings to govern the feed, a feed screw adapt-ed. to convey fuel to said valves, a multiported inemoer adapted to supportsaid casings, and means for stopping the flow of lfuel through any section of said multiported l() member when deeired,

12. ln a eornminuted fuel feeder, the cornhination et a rotary feed screw, a casing inclosing a seetionof the same and having a discharge outlet., a longitudinally slidable 105 valve sleeve eurrormding said screw in said casing, the inner end ot' said sleeve having ishaped notches cut therein and the outer end projecting' outside said casing andv being cut away at the top to receive the fuel, a v110 sleeve fixed in said casing With its inner end surrounding `the notched end of 4the valve sleeve, a hearing member, open at its iop, surrounding" and supporting said projectint,Y end of the valve sleeve, and means H to reciprocate the latter.

CHARLES L. HEISLER. Witnesses:

Hentai* E. YOUNG, RALPH B. BURTONe 

